From Patterns and Practices we can expect soon an Enterprise Library. This is a single application block that will integrate the most used application blocks. For the first release it will include:

• Data Access
• Exception Handling
• Caching
• Configuration
• Logging
• Security
• Cryptography

I am convinced that the Enterprise Library will be the defacto standard application block for each application/project. All the functionalities are so fundamental that you can't without it. Like the site mentions, it enforces Consistency, Extensibility, Ease of Use and Integration. The GodDotNet workspace for Enterprise Library can be found here.